Abstract: Electromagnetic relay having a bobbin (1), a mobile contact sheet (2) which is displaceable between two fixed contact sheets (3), an armature (11), a magnetic core (43) and a signaling plate (4) indicating the operation mode of the relay. Means are provided to situate the various parts such as the base (23), the support (9), the carcass (5) wherein a receptacle (6) may receive an interchangeable circuit plate (7). The bobbin-carrier spool (44) has six terminals at its upper part, two of which are used for the connection of the terminals of the bobbin, a third terminal used for relays having a second winding, the two terminals (19) and a sixth terminal (44) which is an auxiliary control terminal. Means are provided to indicate the relay operation mode through a LED (54) and to identify the relay by means of a removable label (56) placed on he cover (8).